It’s because lower frequencies get reflected by atmospheric bands and cannot penetrate to get through to the satellite . … Therefore, mobile-to-base station (uplink) frequencies are lower than base station-to-mobile(downlink) frequencies.
Read moreCan the same frequency be used for uplink and downlink communication?
The uplink and downlink transmitters use separate frequency bands for transmissions ; therefore, both downlink and uplink transmitters can transmit at all times and at the same time [3].
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